Pump

ABSTRACT

A pump is capable of screening out coarse contaminants from fluid, and includes a pump housing with a fluid-entering portion and a fluid-exiting portion, a screen unit mounted on the fluid-entering portion and having holes for screening out the coarse contaminants from the fluid, and a filter unit mounted on the fluid-exiting portion and having holes for filtering out fine contaminants from the fluid. The holes of the screen unit are larger than the holes of the filter unit.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a pump, more particularly to a pump that is capable of screening out coarse contaminants from fluid.

2. Description of the Related Art

Referring to FIG. 1, an above-ground swimming pool 1′ is provided with a pump 2′ for circulating water from the above-ground swimming pool 1′ to a processing unit, such as a heater, and for pumping the processed water back to the above-ground swimming pool 1′. The conventional pump 2′ is usually provided with a filter unit (not shown) for filtering out fine contaminants from water. However, in addition to the fine contaminants, the water also contains coarse contaminants, such as leaves, little branches, pebbles, and the like, which can block the filter unit. Therefore, an additional screen member 3′ is required to screen out the coarse contaminants from water before the latter enters into the pump 2′ . Therefore, an additional cost is required for the screen member 2′ .

SUMMARY OF THE INVENTION

Therefore, the object of this invention is to provide a pump that can overcome the aforesaid drawback associated with the prior art.

The pump capable of screening out coarse contaminants from fluid according to this invention includes a pump housing with a fluid-entering portion and a fluid-exiting portion, a screen unit mounted on the fluid-entering portion and having holes for screening out the coarse contaminants from the fluid, and a filter unit mounted on the fluid-exiting portion and having holes for filtering out fine contaminants from the fluid. The holes of the screen unit are larger than the holes of the filter unit.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which:

FIG. 1 is a schematic view a conventional pump used for an above-ground swimming pool;

FIG. 2 is an exploded perspective view of the preferred embodiment of the pump according to this invention;

FIG. 3 is an assembled perspective view of the preferred embodiment; and

FIG. 4 is a schematic partly sectional view to illustrate the preferred embodiment in a state of use.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 2 and 3, the preferred embodiment of a pump capable of screening out coarse contaminants from fluid according to this invention is shown to include a pump housing 1, a screen unit 2, and a filter unit 3.

The pump housing 1 includes a fluid-entering portion 11 and a fluid-exiting portion 12. The fluid-entering portion 11 includes a first tubular wall 13 which defines a receiving space 10, and which has a first end 132 connected to the pump housing 1 and a second end 133 extending away from the pump housing 1, and a first inlet port 131 projecting from the first tubular wall 13 between the first and second ends 132,133 for connecting with a tubular member (not shown) to permit transport of the fluid into the receiving space 10 of the pump housing 1. The fluid-entering portion 11 further includes a first opening 130 formed at the second end 133 of the first tubular wall 13. The first tubular wall 13 is formed with an outer threaded portion 14 proximate to the second end 133 thereof. The fluid-entering portion 11 further includes a cover 15 having an inner threaded portion 151 for threadedly engaging the outer threaded portion 14 of the first tubular wall 13 such that the cover 15 can close removably the first opening 130.

The fluid-exiting portion 12 includes a threaded annular flange 16 extending from the pump housing 1, and a cap 17 having an inner threaded portion (not shown) for threadedly engaging the threaded annular flange 16. The cap 17 further has an outlet port 171 at the top thereof for connecting with a tubular member (not shown) to permit transport of the fluid from the pump housing 1.

The screen unit 2 is mounted on the fluid-entering portion 11 and has holes 22 for screening out the coarse contaminants from the fluid. The size of each of the holes 22 of the screen unit 2 is smaller than that of the first inlet port 131. The screen unit 2 includes a second tubular wall 24 surrounded by the first tubular wall 13, a second inlet port 21 projecting toward the first inlet port 131 from the second tubular wall 24, and an end wall 25 connected to the second tubular wall 24 proximate to the first end 132 of the first tubular wall 13. The holes 22 of the screen unit 2 are formed in the second tubular wall 24 and the end wall 25. The screen unit 2 further has a second opening 26 opposite to the end wall 25. The second tubular wall 24 has a rim 27, which projects outward and around the second tubular wall 24 proximate to the second opening 26. The rim 27 is seated on the second end 133 of the first tubular wall 13. The screen 2 further has a handle 23 pivotally mounted on the second tubular wall 24 proximate to the second opening 26.

The filter unit 3 is mounted on the fluid-exiting portion 12, and has holes for filtering out fine contaminants from the fluid. The holes 22 of the screen unit 2 are larger than the holes of the filter unit 3. The filter unit 3 is covered by the cap 17, and further has a central passage 32 fluidly communicated with the outlet port 171 of the cap 17.

Referring to FIG. 4, in use, as indicated by the arrows in FIG. 4, the fluid first enters into the screen unit 2 through the first inlet port 131 and the second inlet port 21. The coarse contaminants contained in the fluid can be filtered out from the fluid by the screen unit 2 when the fluid passes through the screen unit 2 via the holes 22 of the screen unit 2. The fluid passing through the screen unit 2 is then passed through the filter unit 3 so as to filter out the fine contaminants from the fluid, and is subsequently transported out of the pump through the central passage 32 of the filter unit 3 and the outlet port 171 of the cap 7. In view of the aforesaid, the coarse contaminants contained in the fluid can be first filtered out from the latter by the screen unit 2 so as to prevent the holes of the filter unit 3 from being blocked by the coarse contaminants. Therefore, the drawback of the prior art can be avoided. Furthermore, since the cover 15 is removable, cleaning of the screen unit 2 can be conveniently conducted whenever necessary.

Preferably, the cover 15 and the cap 17 are made of transparent plastics so that user is able to determine whether the screen unit 2 and the filter unit 3 have to be cleaned or replaced by simply viewing through the cover 15 and the cap 17. While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements. 

1. A pump capable of screening out coarse contaminants from fluid, said pump comprising: a pump housing including a fluid-entering portion and a fluid-exiting portion; a screen unit mounted on said fluid-entering portion and having holes for screening out the coarse contaminants from the fluid; and a filter unit mounted on said fluid-exiting portion and having holes for filtering out fine contaminants from the fluid, wherein said holes of said screen unit are larger than said holes of said filter unit.
 2. The pump as claimed in claim 1, wherein said fluid-entering portion includes a first tubular wall which has a first end connected to said pump housing and a second end extending away from said pump housing, and a first inlet port projecting from said first tubular wall between said first and second ends.
 3. The pump as claimed in claim 2, wherein said screen unit includes a second tubular wall surrounded by said first tubular wall, a second inlet port projecting toward said first inlet port from said second tubular wall, and an end wall connected to said second tubular wall proximate to said first end of said first tubular wall, said holes of said screen unit being formed in said second tubular wall and said end wall.
 4. The pump as claimed in claim 3, wherein said fluid-entering portion further includes a first opening formed at said second end of said first tubular wall, said screen unit further having a second opening opposite to said end wall.
 5. The pump as claimed in claim 4, wherein said second tubular wall has a rim which projects outward and around said second tubular wall proximate to said second opening, said rim being seated on said second end of said first tubular wall.
 6. The pump as claimed in claim 4, wherein said fluid-entering portion further includes a cover removably covering said first opening.
 7. The pump as claimed in claim 6, wherein said cover is transparent.
 8. The pump as claimed in claim 4, wherein said screen unit further has a handle pivotally mounted on said second tubular wall proximate to said second opening. 